Static eliminating system



July 6 1926. 1,591,601

A. s. ALBRO 4 STATIC ELIMINATING SYSTEM F1164 Sept. 12, 1922 MM. w 7 m.r// fiW? w Patented July 6, 1926.

AZNIES S. -.ALBRO, OF WASHINGTON; DISTRICT OF COLUMBIA.

STATIC ELIMINATING SYSTEM- Application filed September 12, 1922.SerialNo. 587,734.

This inventionrelates to antenna systems and has more particularreference to interior antenna installations.

In those. cases where the usual Marconi aerial has been disadvantageous,whether for military or other reasons, it has been been suggested thatcoil or loop antennae be employed In contradistinction the presentinvention'comprises a system for the reception of signals. particularlyWhere neither loop nor aerial as such, is employed, and yet the strengthof'signal is remarkably great and moreover"substantiallyfreefrom staticor' spark disturbances of the decremental ar X l The systemaccordingtothe present invention comprises attaching one end of areceiver set to the metallic structure either of a building or apartmenthouse and employiug a balancing condenser or counterpoise connectionwithin the same building structure from" the other end of the set placed.vvithin the ,building or the like. In this" way' it is'found thathardly any length of wire at all is required and remarkably clear andstrong signals, especially of the continuous wave type, can be receivedthrough the strongest type of local spark set interference.

Naturally in a building, or apartment house or the like, of severalstories there is one particular floor for which a simple connection atthe one end to a radiator or the like. and at the other end to a bedspring or the like, adjustably arranged as to height from the floor orwalls, will give the strongest type of signals. The internal tuning ofthe set by means of the above system becomes exceedingly sharp, so muchso, that on the sixth floor of an apartment house in Washington, D. 0.,it Was possible to entirely tune out the Arlington Spark Set Station andreceive distance signals from Schenectady, Detroit, etc. The onlyconnections made were a direct wire leading from the set to theradiators, up to four in number, in the apartment, and a bed spring, orsprings, metallic circuit or the like as insulated counterpoise for theother end of the set.

The remarkable freedom from static interference according to the presentinvention is possibly to be explained by the iron frame work of thebuilding acting as a Faraday cage with the internal, really single turnloop connection forming as it were an underground type of antenna as thereceptor.

In other words, the ground connection the radiators and the like, withthe present invention form part of a tuned'receiving single turn throughthe counter-poise capacity" to ground. .7

There would seem therefore to be present a number of peculiar antennaeffects for it is well known that the vertical frame work of a buildingacts as an unloaded antenna. In addition thereto there is What might becalled the underground effect, and a thirdly there is present the singlelooptuned effect already referred to.

iowever, in order better to understand my invention I have attachedhereto a number of drawings forming part of this specification in which7 Figure 1 represents. thef metallic frame work of a building forming asit were ing the addition of several units to antenna.

Referring more particularly to the drawing, it. will be seen that inFigure 1, the framework of the building is used as an antenna A and theradio set S is connected to a vertical member of the framework. Thecounterpoise C is also connected to the set S and is shown spaced fromone of the floors of the building. Figure 3 shows diagrammatically thislayout. I

An actual layout of the present invention is best shown in Figure 2, inwhich the antenna terminal A of the radio set is connected to theradiator of the heating system and the ground terminal 3 is connected tothe counterpoise O, in this case a bed spring. In order to vary thecapacity of both the antenna and counterpoise, additional units may beadded as indicated at A and C in this figure.

It should be pointed out as a feature of the system contemplated that itappears to Work much better when the receiving set includes the use ofan adjusting antenna condenser. Under these circumstances there is amaterial advantage ofiered in connecting up the antenna and groundconnections in the particular manner indicated in Figure 4 of thedrawings.

With the radiators of the building forming an antenna connection to theantenna condenser A C (see Figure 4-) of the sets, the ground connectionG of the primary is preferably adjustably connected to the staticeliminating counterpoise illustrated in the drawings; Such adjustablecounterpoise can be made of a plurality of bed springs, or the like,connected in parallel as by means of the connection C (see Figure 2) asthe conditions of the weather (static) or the distance from the sendingstation may warrant. It would appear that the question of necessaryadjustment for a particular station resolves itself into the matter ofstatic introducing influences between the sending and receiving stationsin question. In the same way the extent of aerial connections can alsobe effected by means of the lead A (see Figures 2 and 5) serving to makegreater or less contact with the frame work of the building.

In operation therefore the antenna side of a set S preferably includingan antenna tuning condenser A C is connected to a radiator, or desirednumber of radiators,

with the ground side of the set connected to a counterpoise, or desirednumber of counterpoises, within the building or frame work. Tuning for awave length is then effected in the usual manner including the properadjustment of the antenna condenser. Thereafter the counterpoiseconnection is suitably varied for a given station and also foratmospheric conditions, static, prevalent at the time.

Having described the nature of my invention what I claim is:

In combination with a grounded equivalent of a Faraday cage adapted toact as an unloaded vertical antenna, a radio receiving apparatusattached through a removable conducting element of said cage to apointvertieally along the frame work of said cage, means forcapacitively and adjustably connecting the other end of said receivingset to one or more points on a second removable element of said cage onsubstantially the same horizontal lines as the first named connection,said second element by means of its connection being adapted to act as acounterpoise to correspond with a particular transmitting station at agiven dis tance, the capacity of said counterpoise being different thanthat of the condenser of said antenna.

In testimony whereof he afiixes his signature.

AMES S. ALBRO.

